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Re: Satellite Mode Duty Cycles...




>Unprocessed SSB ~ 15% Duty Cycle
>Speech Processed SSB ~ 35% Duty Cycle
>Standard CW (PARIS Format) ~ 44% Duty Cycle
>Farnsworth Format CW (13 WPM with 5 WPM spacing) ~ much better than standard 
>CW


This is some good information, but I think duty cycle is only part of the picture. Readability is also an important factor to consider. The readability of a CW signal can still be obtained with overall power reduction much better than SSB at the same power levels. Duty cycle has little to do with it when you consider the amount of power required on an uplink in order to achieve a level of readability. Duty cycle is only the percentage a transmitter is on and doesn't take in to consideration the level of output power (Tx on / (Tx on + Tx off)). Most specs are for duty cycles at maximum output power the transmitter is rated rather than the output power level required for readability. That's why I feel that even the slower CW signals on AO-7 are more power efficient than SSB if levels are kept low but still enough to achieve readability.

Allen Cutts, N4OZI


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